org.apache.wicket
Class Page

java.lang.Object
  org.apache.wicket.Component
      org.apache.wicket.MarkupContainer
          org.apache.wicket.Page

All Implemented Interfaces:

java.io.Serializable, IClusterable, IConverterLocator, IRedirectListener, IRequestListener, IPageMapEntry

Direct Known Subclasses:

WebPage

public abstract class Page
extends MarkupContainer
implements IRedirectListener, IPageMapEntry

Abstract base class for pages. As a MarkupContainer subclass, a Page can contain a component hierarchy and markup in some markup language such as HTML. Users of the framework should not attempt to subclass Page directly. Instead they should subclass a subclass of Page that is appropriate to the markup type they are using, such as WebPage (for HTML markup).

• Construction - When a page is constructed, it is automatically added to the current PageMap in the Session. When a Page is added to the Session's PageMap, the PageMap assigns the Page an id. A PageMap is roughly equivalent to a browser window and encapsulates a set of pages accessible through that window. When a popup window is created, a new PageMap is created for the popup.
• Identity - The Session that a Page is contained in can be retrieved by calling Page.getSession(). Page identifiers start at 0 for each PageMap in the Session and increment as new pages are added to the map. The PageMap-(and Session)-unique identifier assigned to a given Page can be retrieved by calling getId(). So, the first Page added to a new user Session will always be named "0".
• LifeCycle - Subclasses of Page which are interested in lifecycle events can override onBeginRequest, onEndRequest() and onModelChanged(). The onBeginRequest() method is inherited from Component. A call to onBeginRequest() is made for every Component on a Page before page rendering begins. At the end of a request (when rendering has completed) to a Page, the onEndRequest() method is called for every Component on the Page.
• Nested Component Hierarchy - The Page class is a subclass of MarkupContainer. All MarkupContainers can have "associated markup", which resides alongside the Java code by default. All MarkupContainers are also Component containers. Through nesting, of containers, a Page can contain any arbitrary tree of Components. For more details on MarkupContainers, see MarkupContainer.
• Bookmarkable Pages - Pages can be constructed with any constructor when they are being used in a Wicket session, but if you wish to link to a Page using a URL that is "bookmarkable" (which implies that the URL will not have any session information encoded in it, and that you can call this page directly without having a session first directly from your browser), you need to implement your Page with a no-arg constructor or with a constructor that accepts a PageParameters argument (which wraps any query string parameters for a request). In case the page has both constructors, the constructor with PageParameters will be used.
• Models - Pages, like other Components, can have models (see IModel). A Page can be assigned a model by passing one to the Page's constructor, by overriding initModel() or with an explicit invocation of setModel(). If the model is a CompoundPropertyModel, Components on the Page can use the Page's model implicitly via container inheritance. If a Component is not assigned a model, the initModel() override in Component will cause that Component to use the nearest CompoundModel in the parent chain, in this case, the Page's model. For basic CompoundModels, the name of the Component determines which property of the implicit page model the component is bound to. If more control is desired over the binding of Components to the page model (for example, if you want to specify some property expression other than the component's name for retrieving the model object), BoundCompoundPropertyModel can be used.
• Back Button - Pages can support the back button by enabling versioning with a call to setVersioned(boolean). If a Page is versioned and changes occur to it which need to be tracked, a verison manager will be installed using the overridable factory method newVersionManager(). The default version manager returned by the base implementation of this method is an instance of UndoPageVersionManager, which manages versions of a page by keeping change records that can be reversed at a later time.
• Security - See IAuthorizationStrategy, SimplePageAuthorizationStrategy

  Author:

  Jonathan Locke, Chris Turner, Eelco Hillenius, Johan Compagner

  See Also:

  WebPage, MarkupContainer, CompoundPropertyModel, BoundCompoundPropertyModel, Component, IPageVersionManager, UndoPageVersionManager, Serialized Form

  Nested Class Summary

  static interface

  Page.IPageSerializer You can set implementation of the interface in the serializer then that implementation will handle the serialization of this page.

  Nested classes/interfaces inherited from class org.apache.wicket.Component

  Component.ComponentModelChange, Component.EnabledChange, Component.IVisitor, Component.VisibilityChange

  Field Summary

  static int	LATEST_VERSION When passed to getVersion(int) the latest page version is returned.
  static java.lang.ThreadLocal	serializer This is a thread local that is used for serializing page references in this page.It stores a Page.IPageSerializer which can be set by the outside world to do the serialization of this page.

  Fields inherited from class org.apache.wicket.Component

  ENABLE, FLAG_RESERVED1, FLAG_RESERVED2, FLAG_RESERVED3, FLAG_RESERVED4, FLAG_RESERVED5, FLAG_RESERVED6, FLAG_RESERVED7, FLAG_RESERVED8, PATH_SEPARATOR, RENDER

  Fields inherited from interface org.apache.wicket.IRedirectListener

  INTERFACE

  Constructor Summary

  protected	Page() Constructor.
  protected	Page(IModel model) Constructor.
  protected	Page(IPageMap pageMap) Constructor.
  protected	Page(IPageMap pageMap, IModel model) Constructor.
  protected	Page(PageParameters parameters) Constructor.

  Method Summary

  void	afterCallComponent(Component component, RequestListenerInterface listener) Called right after a component's listener method (the provided method argument) was called.
  void	beforeCallComponent(Component component, RequestListenerInterface listener) Called just before a component's listener method (the provided method argument) is called.
  void	componentRendered(Component component) Adds a component to the set of rendered components.
  protected void	configureResponse() Set-up response with appropriate content type, locale and encoding.
  void	detachModels() Detaches any attached models referenced by this page.
  void	dirty() Mark this page as dirty in the session
  void	endComponentRender(Component component) THIS METHOD IS NOT PART OF THE WICKET PUBLIC API.
  void	expireOldestVersion() Expire the oldest version of this page
  int	getAjaxVersionNumber()
  short	getAutoIndex() THIS METHOD IS NOT PART OF THE WICKET PUBLIC API.
  int	getCurrentVersionNumber()
  java.lang.String	getId() Gets the id of this component.
  int	getNumericId()
  java.lang.Class	getPageClass()
  IPageMap	getPageMap()
  IPageMapEntry	getPageMapEntry()
  java.lang.String	getPageMapName()
  long	getSizeInBytes()
  boolean	getStatelessHint() Returns whether the page should try to be stateless.
  Page	getVersion(int versionNumber) Override this method to implement a custom way of producing a version of a Page when it cannot be found in the Session.
  int	getVersions()
  java.lang.String	hierarchyAsString()
  void	ignoreVersionMerge() Call this method when the current (ajax) request shouldn't merge the changes that are happening to the page with the previous version.
  protected void	internalOnModelChanged() THIS METHOD IS NOT PART OF THE WICKET PUBLIC API.
  boolean	isBookmarkable() Bookmarkable page can be instantiated using a bookmarkable URL.
  boolean	isErrorPage() Override this method and return true if your page is used to display Wicket errors.
  boolean	isPageStateless() Gets whether the page is stateless.
  protected void	moveToPageMap(IPageMap map) THIS METHOD IS NOT PART OF THE WICKET PUBLIC API.
  protected IPageVersionManager	newVersionManager()
  protected void	onDetach() Called to allow a component to detach resources after use.
  void	onRedirect() Redirect to this page.
  protected void	onRender(MarkupStream markupStream) Renders this container to the given response object.
  void	removePersistedFormData(java.lang.Class formClass, boolean disablePersistence) Convenience method.
  void	renderPage() THIS METHOD IS NOT PART OF THE WICKET PUBLIC API.
  Page	rollbackPage(int numberOfVersions) This returns a page instance that is rollbacked the number of versions that is specified compared to the current page.
  void	setNumericId(int id) THIS METHOD IS NOT PART OF THE WICKET PUBLIC API.
  void	setStatelessHint(boolean value) Sets whether the page should try to be stateless.
  void	startComponentRender(Component component) THIS METHOD IS NOT PART OF THE WICKET PUBLIC API.
  java.lang.String	toString() Get the string representation of this container.

  Methods inherited from class org.apache.wicket.MarkupContainer

  add, addOrReplace, autoAdd, autoAdd, contains, findMarkupStream, get, getAssociatedMarkupStream, getMarkupStream, getMarkupType, hasAssociatedMarkup, internalAdd, isTransparentResolver, iterator, iterator, newMarkupResourceStream, onComponentTagBody, remove, remove, removeAll, renderAll, renderAssociatedMarkup, renderComponentTagBody, replace, setMarkupStream, setModel, size, toString, visitChildren, visitChildren

  Methods inherited from class org.apache.wicket.Component

  add, addStateChange, afterRender, attach, beforeRender, checkComponentTag, checkComponentTagAttribute, checkHierarchyChange, continueToOriginalDestination, debug, detach, detachBehaviors, detachModel, error, exceptionMessage, fatal, findPage, findParent, findParentWithAssociatedMarkup, getApplication, getBehaviors, getBehaviors, getClassRelativePath, getComponentBorder, getConverter, getConverter, getEscapeModelStrings, getFeedbackMessage, getFlag, getFlag, getInnermostModel, getInnermostModel, getLocale, getLocalizer, getMarkupAttributes, getMarkupId, getMetaData, getModel, getModelComparator, getModelObject, getModelObjectAsString, getModelObjectAsString, getOutputMarkupId, getPage, getPageFactory, getPageRelativePath, getParent, getPath, getRenderBodyOnly, getRequest, getRequestCycle, getResponse, getSession, getString, getString, getString, getStyle, getVariation, hasBeenRendered, hasErrorMessage, hasFeedbackMessage, info, initModel, internalAttach, internalDetach, internalOnAttach, internalOnDetach, isActionAuthorized, isAncestorOf, isAttached, isBehaviorAccepted, isEnableAllowed, isEnabled, isIgnoreAttributeModifier, isRenderAllowed, isStateless, isVersioned, isVisible, isVisibleInHierarchy, locateMarkupStream, markRendering, modelChanged, modelChanging, newPage, newPage, onAfterRender, onAttach, onBeforeRender, onBeginRequest, onComponentTag, onEndRequest, onModelChanged, onModelChanging, prepareForRender, redirectToInterceptPage, remove, remove, render, render, renderComponent, renderComponent, renderComponentTag, rendered, renderHead, replaceComponentTagBody, replaceWith, sameInnermostModel, sameInnermostModel, setAuto, setComponentBorder, setEnabled, setEscapeModelStrings, setFlag, setFlag, setIgnoreAttributeModifier, setMarkupId, setMetaData, setModelObject, setOutputMarkupId, setOutputMarkupPlaceholderTag, setRedirect, setRenderBodyOnly, setResponsePage, setResponsePage, setResponsePage, setVersioned, setVisible, urlFor, urlFor, urlFor, urlFor, urlFor, urlFor, visitParents, warn, wrap

  Methods inherited from class java.lang.Object

  clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

  Methods inherited from interface org.apache.wicket.session.pagemap.IPageMapEntry

  getPage

  Field Detail

  LATEST_VERSION

  public static final int LATEST_VERSION

  When passed to getVersion(int) the latest page version is returned.

  See Also:

  Constant Field Values

  serializer

  public static final java.lang.ThreadLocal serializer

  This is a thread local that is used for serializing page references in this page.It stores a Page.IPageSerializer which can be set by the outside world to do the serialization of this page.

  Constructor Detail

  Page

  protected Page()

  Constructor.

  Page

  protected Page(IModel model)

  Constructor.

  Parameters:

  model - See Component

  See Also:

  Component.Component(String, IModel)

  Page

  protected Page(IPageMap pageMap)

  Constructor.

  Parameters:

  pageMap - The page map to put this page in

  Page

  protected Page(IPageMap pageMap,
                 IModel model)

  Constructor.

  Parameters:

  pageMap - the name of the page map to put this page in

  model - See Component

  See Also:

  Component.Component(String, IModel)

  Page

  protected Page(PageParameters parameters)

  Constructor.

  Parameters:

  parameters - externally passed parameters

  See Also:

  PageParameters

  Method Detail

  afterCallComponent

  public void afterCallComponent(Component component,
                                 RequestListenerInterface listener)

  Called right after a component's listener method (the provided method argument) was called. This method may be used to clean up dependencies, do logging, etc. NOTE: this method will also be called when beforeCallComponent(Component, RequestListenerInterface) or the method invocation itself failed.

  Parameters:

  component - the component that is to be called

  listener - the listener of that component that is to be called

  beforeCallComponent

  public void beforeCallComponent(Component component,
                                  RequestListenerInterface listener)

  Called just before a component's listener method (the provided method argument) is called. This method may be used to set up dependencies, enforce authorization, etc. NOTE: if this method fails, the method will not be excuted. Method afterCallComponent(Component, RequestListenerInterface) will always be called.

  Parameters:

  component - the component that is to be called

  listener - the listener of that component that is to be called

  componentRendered

  public final void componentRendered(Component component)

  Adds a component to the set of rendered components.

  Parameters:

  component - The component that was rendered

  detachModels

  public void detachModels()

  Detaches any attached models referenced by this page.

  Overrides:

  detachModels in class Component

  dirty

  public final void dirty()

  Mark this page as dirty in the session

  endComponentRender

  public final void endComponentRender(Component component)

  THIS METHOD IS NOT PART OF THE WICKET PUBLIC API. DO NOT CALL. This method is called when a component was rendered standalone. If it is a markupcontainer then the rendering for that container is checked.

  Parameters:

  component -

  expireOldestVersion

  public final void expireOldestVersion()

  Expire the oldest version of this page

  getAjaxVersionNumber

  public final int getAjaxVersionNumber()

  Returns:

  The current ajax version number of this page.

  getAutoIndex

  public final short getAutoIndex()

  THIS METHOD IS NOT PART OF THE WICKET PUBLIC API. DO NOT CALL IT. Get a page unique number, which will be increased with each call.

  Returns:

  A page unique number

  getCurrentVersionNumber

  public final int getCurrentVersionNumber()

  Returns:

  The current version number of this page. If the page has been changed once, the return value will be 1. If the page has not yet been revised, the version returned will be 0, indicating that the page is still in its original state.

  getId

  public final java.lang.String getId()

  Description copied from class: Component

  Gets the id of this component.

  Overrides:

  getId in class Component

  Returns:

  The id of this component

  See Also:

  Component.getId()

  getNumericId

  public int getNumericId()

  Specified by:

  getNumericId in interface IPageMapEntry

  Returns:

  A stable identifier for this page map entry

  See Also:

  IPageMapEntry.getNumericId()

  getPageClass

  public final java.lang.Class getPageClass()

  Specified by:

  getPageClass in interface IPageMapEntry

  Returns:

  The class of page stored in this page map entry (which can be used by an eviction strategy to prioritize evictions)

  See Also:

  IPageMapEntry.getPageClass()

  getPageMap

  public final IPageMap getPageMap()

  Returns:

  Returns the PageMap that this Page is stored in.

  getPageMapEntry

  public IPageMapEntry getPageMapEntry()

  Returns:

  Get a page map entry for this page. By default, this is the page itself. But if you know of some way to compress the state for the page, you can return a custom implementation that produces the page on-the-fly.

  getPageMapName

  public final java.lang.String getPageMapName()

  Returns:

  getSizeInBytes

  public final long getSizeInBytes()

  Overrides:

  getSizeInBytes in class Component

  Returns:

  Size of this page in bytes

  getStatelessHint

  public final boolean getStatelessHint()

  Returns whether the page should try to be stateless. To be stateless, getStatelessHint() of every component on page (and it's behavior) must return true and the page must be bookmarkable.

  Overrides:

  getStatelessHint in class Component

  Returns:

  whether the component can be stateless

  See Also:

  Component.getStatelessHint()

  getVersion

  public Page getVersion(int versionNumber)

  Override this method to implement a custom way of producing a version of a Page when it cannot be found in the Session.

  Parameters:

  versionNumber - The version desired

  Returns:

  A Page object with the component/model hierarchy that was attached to this page at the time represented by the requested version.

  getVersions

  public final int getVersions()

  Returns:

  Number of versions of this page

  hierarchyAsString

  public final java.lang.String hierarchyAsString()

  Returns:

  This page's component hierarchy as a string

  ignoreVersionMerge

  public final void ignoreVersionMerge()

  Call this method when the current (ajax) request shouldn't merge the changes that are happening to the page with the previous version. This is for example needed when you want to redirect to this page in an ajax request and then you do want to version normally.. This method doesn't do anything if the getRequest().mergeVersion doesn't return true.

  isBookmarkable

  public boolean isBookmarkable()

  Bookmarkable page can be instantiated using a bookmarkable URL.

  Returns:

  Returns true if the page is bookmarkable.

  isErrorPage

  public boolean isErrorPage()

  Override this method and return true if your page is used to display Wicket errors. This can help the framework prevent infinite failure loops.

  Returns:

  True if this page is intended to display an error to the end user.

  isPageStateless

  public final boolean isPageStateless()

  Gets whether the page is stateless. Components on stateless page must not render any statefull urls, and components on statefull page must not render any stateless urls. Statefull urls are urls, which refer to a certain (current) page instance.

  Returns:

  Whether to page is stateless

  onRedirect

  public final void onRedirect()

  Redirect to this page.

  Specified by:

  onRedirect in interface IRedirectListener

  See Also:

  IRedirectListener.onRedirect()

  removePersistedFormData

  public final void removePersistedFormData(java.lang.Class formClass,
                                            boolean disablePersistence)

  Convenience method. Search for children of type fromClass and invoke their respective removePersistedFormData() methods.

  Parameters:

  formClass - Form to be selected. Pages may have more than one Form.

  disablePersistence - if true, disable persistence for all FormComponents on that page. If false, it will remain unchanged.

  See Also:

  Form.removePersistentFormComponentValues(boolean)

  renderPage

  public final void renderPage()

  THIS METHOD IS NOT PART OF THE WICKET PUBLIC API. DO NOT CALL IT.

  rollbackPage

  public final Page rollbackPage(int numberOfVersions)

  This returns a page instance that is rollbacked the number of versions that is specified compared to the current page. This is a rollback including ajax versions.

  Parameters:

  numberOfVersions - to rollback

  Returns:

  rollbacked page instance

  setNumericId

  public final void setNumericId(int id)

  THIS METHOD IS NOT PART OF THE WICKET PUBLIC API. DO NOT CALL. Set the id for this Page. This method is called by PageMap when a Page is added because the id, which is assigned by PageMap, is not known until this time.

  Specified by:

  setNumericId in interface IPageMapEntry

  Parameters:

  id - The id

  setStatelessHint

  public final void setStatelessHint(boolean value)

  Sets whether the page should try to be stateless. To be stateless, getStatelessHint() of every component on page (and it's behavior) must return true and the page must be bookmarkable.

  Parameters:

  value - whether the page should try to be stateless

  startComponentRender

  public final void startComponentRender(Component component)

  THIS METHOD IS NOT PART OF THE WICKET PUBLIC API. DO NOT CALL. This method is called when a component will be rendered standalone.

  Parameters:

  component -

  toString

  public java.lang.String toString()

  Get the string representation of this container.

  Overrides:

  toString in class MarkupContainer

  Returns:

  String representation of this container

  See Also:

  Component.toString()

  configureResponse

  protected void configureResponse()

  Set-up response with appropriate content type, locale and encoding. The locale is set equal to the session's locale. The content type header contains information about the markup type (@see #getMarkupType()) and the encoding. The response (and request) encoding is determined by an application setting (@see ApplicationSettings#getResponseRequestEncoding()). In addition, if the page's markup contains a xml declaration like <?xml ... ?> an xml declaration with proper encoding information is written to the output as well, provided it is not disabled by an applicaton setting (@see ApplicationSettings#getStripXmlDeclarationFromOutput()).

  Note: Prior to Wicket 1.1 the output encoding was determined by the page's markup encoding. Because this caused uncertainties about the /request/ encoding, it has been changed in favour of the new, much safer, approach. Please see the Wiki for more details.

  internalOnModelChanged

  protected final void internalOnModelChanged()

  THIS METHOD IS NOT PART OF THE WICKET PUBLIC API. DO NOT CALL OR OVERRIDE.

  Overrides:

  internalOnModelChanged in class Component

  See Also:

  Component.internalOnModelChanged()

  moveToPageMap

  protected final void moveToPageMap(IPageMap map)

  THIS METHOD IS NOT PART OF THE WICKET PUBLIC API. DO NOT CALL OR OVERRIDE.

  Parameters:

  map -

  newVersionManager

  protected final IPageVersionManager newVersionManager()

  Returns:

  Factory method that creates a version manager for this Page

  onDetach

  protected void onDetach()

  Description copied from class: Component

  Called to allow a component to detach resources after use. Overrides of this method MUST call the super implementation, the most logical place to do this is the last line of the override method.

  Overrides:

  onDetach in class Component

  See Also:

  Component.onDetach()

  onRender

  protected void onRender(MarkupStream markupStream)

  Renders this container to the given response object.

  Overrides:

  onRender in class MarkupContainer

  Parameters:

  markupStream -